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 Here's an example code that should replicate the error: https: //github. com/s769/petsc-test/tree/master. I tried using the PETSC_FORMAT_NATIVE, but I still get the error. I have a situation where the matrix is created on PETSC_COMM_WORLD
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<div dir="ltr">Here's an example code that should replicate the error: <a href="https://urldefense.us/v3/__https://github.com/s769/petsc-test/tree/master__;!!G_uCfscf7eWS!dWU2gJCvykWqg3TTfkkQOsW3q32Sny3r399zmyr6MCiJQh6_dH-T3IktQLg9fbvc4okbbHP2koQZkzL0fCjOTrC90w$">https://github.com/s769/petsc-test/tree/master</a>.<div><br></div><div>I tried using the PETSC_FORMAT_NATIVE, but I still get the error. I have a situation where the matrix is created on PETSC_COMM_WORLD but only has entries on the first process due to some layout constraints elsewhere in the program. The nodes I'm running on should have more than enough memory to hold the entire matrix on one process, and the error I get is not an out-of-memory error anyway. </div><div><br></div><div>Let me know if you aren't able to build the example.</div><div><br></div><div>I noticed that if I fully distributed the matrix over all processes, then the save works fine. Is there some way to do that after I create the matrix but before saving it?</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Aug 5, 2024 at 1:19 PM Barry Smith <<a href="mailto:bsmith@petsc.dev">bsmith@petsc.dev</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div><div><br></div>   By default PETSc MatView() to a binary viewer uses the "standard" compressed sparse storage format. This is not efficient (or reasonable) for dense matrices and <div>produces issues with integer overflow.<br><div><br></div><div>   To store a dense matrix as dense on disk, use the PetscViewerFormat of PETSC_VIEWER_NATIVE. So for example</div><div><br></div><div>   PetscViewerPushFormat(viewer,PETSC_VIEWER_NATIVE);</div><div>   MatView(mat, viewer);</div><div>   PetscViewerPopFormat(viewer);</div><div><br id="m_3591405006712013394lineBreakAtBeginningOfMessage"><div><br><blockquote type="cite"><div>On Aug 5, 2024, at 1:10 PM, Sreeram R Venkat <<a href="mailto:srvenkat@utexas.edu" target="_blank">srvenkat@utexas.edu</a>> wrote:</div><br><div><div dir="ltr" id="m_3591405006712013394pfptBanners2fszgy" style="writing-mode:revert;color:revert;font-family:revert;font-feature-settings:revert;font-kerning:revert;font-size:revert;font-size-adjust:revert;font-stretch:revert;font-variant-alternates:revert;font-variant-caps:revert;font-variant-east-asian:revert;font-variant-ligatures:revert;font-variant-numeric:revert;font-weight:revert;text-orientation:revert;zoom:revert;letter-spacing:revert;background-blend-mode:revert;background-image:revert;background-position:revert;background-repeat:revert;background-size:revert;border-collapse:revert;box-sizing:revert;break-after:revert;break-before:revert;break-inside:revert;caption-side:revert;clear:revert;columns:revert;column-fill:revert;column-gap:revert;column-rule:revert;column-span:revert;empty-cells:revert;float:revert;image-orientation:revert;isolation:revert;line-break:revert;line-height:revert;list-style:revert;mix-blend-mode:revert;object-fit:revert;object-position:revert;outline:revert;overflow:revert;quotes:revert;table-layout:revert;text-align:left;text-align-last:revert;text-decoration:revert;text-emphasis:revert;text-indent:revert;text-overflow:revert;text-transform:revert;text-underline-position:revert;vertical-align:revert;white-space:revert;word-break:revert;border-spacing:revert;word-spacing:revert;background-clip:revert;background-origin:revert;text-combine-upright:revert;display:block;opacity:revert;background-color:rgb(208,216,220);border-bottom:revert;border-left:revert;border-right:revert;height:revert;max-height:revert;max-width:revert;min-height:revert;width:revert;margin:16px 0px;padding:8px 16px;border-radius:4px;min-width:200px;border-top:4px solid rgb(144,164,174)"><div id="m_3591405006712013394pfptBanners2fszgy" style="writing-mode:unset;color:unset;font-family:unset;font-feature-settings:unset;font-kerning:unset;font-size:unset;font-size-adjust:unset;font-stretch:unset;font-variant-alternates:unset;font-variant-caps:unset;font-variant-east-asian:unset;font-variant-ligatures:unset;font-variant-numeric:unset;font-weight:unset;text-orientation:unset;zoom:unset;letter-spacing:unset;background:unset;background-blend-mode:unset;border-collapse:unset;border:unset;box-sizing:unset;break-after:unset;break-before:unset;break-inside:unset;caption-side:unset;clear:unset;columns:unset;column-fill:unset;column-gap:unset;column-rule:unset;column-span:unset;empty-cells:unset;float:left;image-orientation:unset;isolation:unset;line-break:unset;line-height:unset;list-style:unset;mix-blend-mode:unset;object-fit:unset;object-position:unset;outline:unset;overflow:unset;quotes:unset;table-layout:unset;text-align:unset;text-align-last:unset;text-decoration:unset;text-emphasis:unset;text-indent:unset;text-overflow:unset;text-transform:unset;text-underline-position:unset;vertical-align:unset;white-space:unset;word-break:unset;border-spacing:unset;word-spacing: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